However, since the intestinotrophic hormone GLP-2 and chemokines, such as CXCL5 and stromal cell-derived factor-1 (SDF-1), are also substrates of DPP-4, DPP-4 inhibitors may increase the risk of intestinal carcinogenesis.
CXCL5 (epithelial neutrophil activating peptide-78) which acts as a potent chemoattractant and activator of neutrophil function was reported to play a multifaceted role in tumorigenesis.
Conditioned medium from tumor-derived cells (RL-251) showed high concentration of IL-8, epithelial neutrophil-activating protein-78, Gro alpha, and Gro gamma, angiogenic CXC chemokines with a potential role in tumorigenesis.